The present invention relates to the preparation of amino substituted polymeric hydrocarbons and, more particularly, to a process for forming polymeric products having a hydrocarbon backbone and a large amount of pendant secondary and/or tertiary alkyleneamine groups by the reaction of polymeric hydrocarbons having olefinic groups therein with hydrogen, carbon monoxide, and a primary and/or secondary amine in the presence of a catalytic amount of a Group VIII metal compound.
Catalytic aminomethylation of monoolefins with monomeric secondary monoamines, carbon monoxide and hydrogen is well known and was initially taught by Dr. Walter Reppe in Experimentia, Vol. 5, p. 93 (1949); German Pat. No. 839,800 (1952) and Liebigs Ann. Chem., Vol. 582, p. 148 (1953). The process was, however, of limited value due to the required use of large quantities of toxic iron or nickel carbonyls as the catalyst, the rapid rate of consumption of the catalyst, the slow rate of reaction, poor selectivity and the poor yields of product. Moreover, the reaction was taught to be restricted to monoolefins and to low molecular weight monoamines.
Aminomethylation of other monoolefins has been carried out in the presence of other metal carbonyls, but the reactions have been found to be non-selective and produce, at best, only moderate yields of amines. For example, U.S. Pat. Nos. 2,422,631 and 3,234,283 disclose that lower olefins, carbon monoxide, hydrogen, and a secondary monoamine will form, in low yields, tertiary amines in the presence of cobalt hydrocarbonyl or dicobalt octocarbonyl as well as certain other cobalt compounds.
More recently, U.S. Pat. Nos. 3,513,200 and 4,096,150 have disclosed the utilization of Group VIII metal compounds as suitable compounds to catalyze the reaction between monoamines and monoolefins with hydrogen and carbon monoxide to form low molecular weight monomeric tertiary amines. These reactions, however, generally only provide the desired product in low yields while forming significant amounts of by-products.
In addition, U.S. Pat. No. 4,312,965 may be referred to as teaching the formation of a polymeric product having a mixture of amine and amide pendant groups by contacting a polymer with an amine, carbon monoxide and water in the presence of a rhodium metal compound. The required use of water as the hydrogen source and rhodium as the catalytic metal is taught to provide a means of aminomethylation of the polymeric polyolefin. The process, however, yields a product having low degrees of amine incorporation and, therefore, does not provide for a highly active polymer normally desired for commercial utilization. The above and other references teach that aminomethylation generally leads to the formation of significant quantities of undesired by-products. This is confirmed in general treatises such as: "Carbon monoxide in Organic Synthesis" of Falbe.
In general, the yields of desired amine incorporation in previously formed polymeric material and of monomeric amine products by aminomethylation has been viewed by those skilled in this art as being poor at best.